Super XL-925 ignition system?

[Supercharged86]

Hi Guys, So my '80 925W has the three part ignition system, and I was curious if anyone understands why this system has three parts in total? Why the additional doughnut shaped module with it's own contacts/pickups under the flywheel? Was there a need to over-complicate it (other than to sell more replacement parts, when they failed)? I see this system was later replaced with a single module coil. Just wondering..... Thanks. Steve

[ettrick]

My understanding is it was a better performing system at the time of the saw being made. Yes a newer way and cheaper was designed for later profit in saw manufacture. I think if you only have to replace 1/3 of a system because of a failure, it would be cheaper to maintain than replacing the whole system.
Dan

[Supercharged86]

Well, now that I have the flywheel off, I see there's a second set of magnets on the inside, and there offset from the main magnets on the outside. So this inner module has it's own pickups and set of magnets, what are they up to here? Is this somekind of variable timing system? Interesting but why? Cheers. Steve

[undee70ss]

Probably because it has a timing retard. One piece ignitions we’re not capable of that at that time.

[ettrick]

Wow! It is amazing when you can read just how much engineering goes into a saw. A lot of work is being done by a little package.
Dan

[Supercharged86]

Hey Gregg, Thanks for the info, I hadn't seen that before. I guess that solves the mystery of the three part ignition system. I think I would have to somewhat disagree with their theory on easier starting though. Sure, a "retarded" engine may start easier/quicker but pulling against compression is still pulling against compression. And if it's say 180* then that's still alot to pull against. Decomp'ing it makes it easier, in my opinion.